Who's crystal clear and who's all wet when it to comes to Minnesota weather forecasters?

Tuesday, September 11, 2012

Game, Set and Match: Weather Underground

If you enjoy watching and comparing the various forecasts issued by local and national weather sources, today made for great entertainment. We love it when forecasters separate from the crowd. It gives us something to watch when someone takes a chance.

We began monitoring the forecasts for today last Friday. It was hard not to miss the fact that Weather Underground BestForecast was out on a limb, five degrees higher than any other weather outlet. Comments to a recent post derided Weather Underground's renegade forecast, pronouncing it to be a "joke." Well, they're certain laughing back at WU's San Francisco headquarters in China Basin after today's high reached exactly what WU forecast last Friday. Well done, gentleman.

Here's how far off (under predicted) the various weather sources were based on today's actual temperature and Friday's forecast high.

Wunderground BestForecast: 95 (exact!)

Weather.com: 89 (-6)

Accuweather.com: 85 (-10)

Weather.gov: 89 (-6)

Wcco: 86 (-9)

Kstp: 85 (-10)

Kmsp: 87 (-8)

Kare: 85 (-10)

Strib: 80 (-15)

It's interesting to note that the best local television forecast was 8 degrees off, yet the national and governmental sources, excluding Accuweather, were within 6 degrees. Not a good showing for the locals.

23 comments:

A snapshot of the forecast does not constitute "monitoring". There is no trend information, no view earlier than Friday. Why not start last Tuesday, 7 days before the event? What about an actual review of the state of the forecasting art? What is the "standard" error for a four-day forecast?

What do you mean when you say "Not a good showing for the locals"? Is your message that none of the local forecasters equaled Wunderground's single forecast point?

The shrill whine of this website as it regularly puts forth the least possible effort and then declares that the forecasters failed is tiresome. I had hoped that this blog would fulfill the mission it set for itself and am regularly disappointed. This is the last time I'll come here. I've been fooled too many times. Hopefully the rest of the readers will follow suit.

Good riddance Kevin,and don't let the backspace button hit you in the ass!!!!This blog follows the MSP forecast point and no others,so when Wunderground temps were compared to the locals forecast at MSP it wasnt even close(how can you not see that).Another question for you is why go beyond 5 days,like you suggested,when most mets can't even nail a forecast 48 hours out.Bill keep it up,I appreciate you and the work of this blog,dont let trolls bother you.

Looks as though PD takes the cake for biggest miss(15 degrees)that is a big miss.Bill you may want to start monitoring another Tuesday(this time for chilly weather),next Tuesday the 18th,both PD and NWS have a high of 59,where as Wunderground has 68,that variance is too great to overlook.

This leaves us with a average temp for the month of 72° which is +5.9° above the 30 year average through the first 11 days of the month.

But what is on the horizon? Another warmer than normal weekend is setting up. After that all bets are off. All of the indices that meteorologist's look at are showing a major cooling trend. The Pacific North American Oscillation (PNA) is showing signs of going strongly positive which means a ridge on the west coast, thus higher than normal temps out there. The Arctic Oscillation (AO) is showing signs of going strongly negative which means cooler air could be released from the arctic and be transported down to us. The North American Oscillation (NAO) is also showing signs of going strongly negative which means blocking over eastern Canada to Greenland, thus slowing down the progression to the east of troughs and ridges.

So what does that mean? Without any ridges (warmer than normal temps) being able to work into our area, the troughs (cooler than normal temps) will continue to dive into Minnesota without much moisture to work with, keeping the storm track to our south. Because of this I suspect that we will see some much below normal highs next week, after that they will tend to modify. But without much cloud cover I think that over night lows could be lower that what the models are showing.

So even though we are sitting at +5.9° as I type this, I think this month has a good chance of seeing below normal temps overall. That would break our streak of 15 consecutive months of above normal temps. What do I think of the chances? My head says 50/50, my gut says 60/40 chance of below normal temps for the month.

So Bill....I really think you have a chance of getting out ahead of the local forecaster's. You should start a new thread...Will September temps go below normal for the first time in 15 months?

I wish that monthly forecasts were made by the various forecasters. It's an interesting question, but I'm not sure how to do a comparative evaluation without many providing formal forecasts.

It will be interesting to see if the 5.9 variance can be captured and built back into the negative direction. Given the trend of the last many months, it's hard to argue that September will end up below normal, but it's got to happen some day! (or month)

"wish that monthly forecasts were made by the various forecasters. It's an interesting question, but I'm not sure how to do a comparative evaluation without many providing formal forecasts."

You really don't have to do a comparative evaluation, and I know that this is what this site is all about. Just trying to get a discussion going is all. I suspect our local mets will start talking about it soon.